Well jet device for well testing and developing and the operating method for said well jet device

ABSTRACT

The invention relates to jet device used for extracting oil from wells. The inventive device comprises a packer, a pipe column, a jet pump, a transmitter and a receiver of physical fields. The body of the pump comprises a through stepped channel embodied in a parallel position with respect to the axes of the pipe column and having a seat disposed between steps for arranging a sealing unit, which is provided with an axial channel. Said pump body is also provided with an active nozzle. The axis of the active nozzle is disposed in a parallel position with respect to the axis of the through channel at a distance equal to or higher than 1.1 of the radius thereof. The diameter of the through channel above the seat is 0.5 mm greater than the diameter thereof below said seat. The diameter of the axial channel of the sealing unit is equal to or less than 0.6 of the external diameter thereof. The sealing unit is arranged in such a way that it is movable along a cable above a bit and successfully replaceable by the following functional inserts: a blocking insert, depression insert etc. Said inserts are provided with attachments for transporting them to the pump and extracting therefrom and for arranging instruments and samplers thereon. Said invention makes it possible to optimise the dimensions of the elements of the device and increases the reliability thereof.

FIELD OF INVENTION

[0001] This invention relates to the field of pumping engineering,mainly to well jet devices for oil production and intensification of oilinflow from wells.

PRIOR ART

[0002] Known in the art is a well jet device comprising a jet pumpinstalled on the piping string in the well and a transmitter and areceiver-transducer arranged below the jet pump (RU 2129671 C1).

[0003] From the above source known is a method of operation of a welljet device, which includes lowering in the well a piping string with ajet pump, a packer and a transmitter and a receiver-transducer ofphysical fields, the latter being arranged below the jet pump.

[0004] The known device and method enable to explore wells and pumpvarious extracted media, e.g., oil, out of wells, at the same timeexploring the well, the transmitter and receiver of physical fieldsbeing arranged with the possibility of moving back and forth along thewell relative to the jet pump and the stratum.

[0005] But in some cases this is insufficient for obtaining reliableinformation on the well condition, which reduces the efficiency of worksperformed in order to intensify oil production.

[0006] The closest, as to its technical essence and the achievableresult, to this invention in the part of the device as the object of theinvention is a well jet device for testing and developing wells, whichcomprises a packer, a piping string and a jet pump, the body of the saidpump comprising an active nozzle with a mixing chamber and having astepped through passage with a mounting seat between steps forinstalling a sealing assembly with an axial passage, the said well jetdevice being provided with an transmitter and receiver-transducer ofphysical fields, which is arranged on the jet pump side for entry of themedium pumped out of the well, the output side of the jet pump isconnected to the space surrounding the piping string, the jet pumppassage side for entry of the pumped out medium is connected to theinner cavity of the piping string below the sealing assembly, the inputside of the passage for supplying the working medium to the activenozzle is connected to the inner cavity of the piping string above thesealing assembly, and the through passage of the jet pump is madeparallel to the axis of the piping string (RU 2059891 C1).

[0007] The closest, as to its technical essence and the achievableresult, to this invention in the part of the method is the method ofoperation of a well jet device, which includes installation, on thepiping string, of a packer and a jet pump, in the body of which athrough passage is made with a mounting seat, lowering of the wholeassembly into the well, release of the packer and arrangement of atransmitter and a receiver-transducer of physical fields below the jetpump (RU 2121610 C1).

[0008] The known well jet device and the method of operation of the welljet device enable to carry out various process operations in the wellbelow the level at which the jet pump is installed, including thoseperformed by lowering pressure difference above and below the sealingassembly.

[0009] But, the known well jet device and the method of operation do notenable to exploit the potential of the device in full due to non-optimalsequence of operations and dimension relations of various structuralelements of the well jet device.

DISCLOSURE OF INVENTION

[0010] The objective of this invention is to optimize the dimensions ofvarious components of the construction of the well jet device and thesequence of operations when carrying out works on intensifying the wellexploitation and, owing to it, to raise the efficiency of well jetdevice operation in developing and testing wells.

[0011] The stated objective in the part of the device as the object ofthe invention is achieved owing to the fact that the well jet devicecomprises a packer, a piping string and a jet pump, in the body of whichan active nozzle with a mixing chamber are arranged and a steppedthrough passage is made with a mounting seat between steps forinstalling a sealing assembly having an axial channel, the said devicebeing provided with a transmitter and a receiver-transducer of physicalfields, which is arranged at the jet pump side for entry of the mediumpumped out of the well, the jet pump output side is connected to thespace around the piping string, the input side of the jet pump passagefor supplying the pumped out medium is connected to the inner cavity ofthe piping string below the sealing assembly, and the input side of thepassage for supplying the working medium to the active nozzle isconnected to the inner cavity of the piping string above the sealingassembly, and the through passage of the jet pump is made parallel tothe axis of the piping string, the axis of the active nozzle beingparallel to the axis of the through passage and being located at adistance equal at least 1.1 radii of the bigger step of the throughpassage from the latter; the diameter of the bigger step in the throughpassage, which is located above the mounting seat, is at least 0.5 mmgreater than the diameter of the step in the through passage, which islocated below the mounting seat; the sealing assembly is arranged on thewell-logging cable or on a wire fed through the axial passage andinstalled with the possibility of being replaced, e.g., in turns, by thefunctional inserts, namely, a hydrostatic testing insert, a depressioninsert, a blocking insert, an insert for recording stratum pressurerestoration curves and an insert for hydrodynamic impact on the stratum;the diameter of the axial passage in the sealing assembly is not greaterthan 0.6 outer diameter of the sealing assembly; the axes of the sealingassembly and the functional inserts are aligned with the axis of thethrough passage in the jet pump; the functional inserts are made withthe possibility of installing on them autonomous well instruments andsampling devices and are made with a tool for delivery and removal ofthem from the jet pump with the use of cable equipment, the sealingassembly being installed with the possibility of moving it along thewell-logging cable or a wire above the cap on which the transmitter andreceiver-transducer of physical fields is arranged, the latter beingconnected to the well-logging cable cap with the possibility of beingreplaced by other well instruments, e.g., a perforator, an ultrasonictransmitter, a sampling device, a thermometer, a pressure gauge, whichall may be connected, either in turns or jointly, to the well-loggingcable or a wire.

[0012] The stated objective in the part of the method as the object ofthe invention is achieved owing to the fact that in the method ofoperation of the well jet unit includes installation on the pipingstring of a packer and a jet pump having a through passage with amounting seat, lowering of that assembly into the well, release of thepacker and arrangement in the well, below the jet pump, of a transmitterand receiver-transducer of physical fields, the said transmitter andreceiver-transducer of physical fields being lowered together with asealing assembly arranged on the well-logging cable or a wire above thecap on which with the transmitter and receiver-transducer is installed,when lowering into the well, the transmitter and receiver-transducer ofphysical fields is used for background measurements of temperature andother physical fields before the well bottom, the sealing assembly isinstalled onto the mounting seat in the through passage without impedingthe back and forth motion of the well-logging cable or wire, then thetransmitter and receiver-transducer of physical fields is arranged inthe stratum interval under exploration and, by supplying the workingmedium to the nozzle of the jet pump, several values of pressuredrawdown on the stratum are successively created, and, at each itsvalue, bottom-hole pressures, compositions of the fluid coming from thestratum and the well flow rate are measured, after which the parametersof physical fields are recorded by moving the transmitter andreceiver-transducer of physical fields along the well axis in the speedrange from 0.1 to 100 meters per minute and at bottom-hole pressureschanging stepwise from the stratum pressure to 0.01 stratum pressure,the transmitter and receiver transformer of physical fields being movedalong the well axis both when the jet pump is operated and when it isshut down, then the transmitter and receiver-transducer of physicalfields is lifted out of the well, and the functional insert forrecording stratum pressure restoration curves is lowered, the saidinsert being provided with a pressure sensor and a sampling device,installed in the through passage of the jet pump, a required pressuredrawdown on the stratum is created with the use of the jet pump, and,after sharp stopping of supplying the liquid working medium to the jetpump, a stratum pressure restoration curve for the well zone under thepacker is recorded, said recording of stratum pressure restorationcurves may be done repeatedly at different pressure drawdown on thestratum; after that the results are processed, and a decision is takenwhether repair works on the well are necessary, such works beingconducted with the use of the jet pump and the alternatively appliedfunctional inserts being lowered into the well with the sealing assemblyon the well-logging cable or a wire and with, e.g., a perforator, anultrasonic transmitter, a sampling device, a thermometer and a pressuregauge, and after completion of the said works the cycle of wellexploration is repeated.

[0013] The analysis of the well jet device has shown that thereliability and efficiency of its operation may be improved both bymaking various components of the device under strictly defineddimensions and by carrying out works in the well in a strictly definedsuccession. During the operation of the device different well modes arestudied. It is required to install and remove the sealing assembly, tomove the transmitter and receiver-transducer of physical fields alongthe well. It has been found that it is advisable to make the diameter ofthe bigger step in the through passage, which is located above themounting seat for the sealing assembly, at least 0.5 mm greater than thediameter of the step in the through passage, which is located below themounting seat, and the diameter of the axial passage in the sealingassembly should not exceed 0.6 outer diameter of the sealing assembly.In the result, the sealing assembly is securely installed on themounting seat and possible overflows through the sealing assembly areminimized. The arrangement of the active nozzle axis at a distance equalat least 1.1 radii of the bigger step in the through passage, whenmaking the nozzle axis parallel to the axis of the through passage,enables to determine the least possible distance between the axis of thenozzle and that of the through passage of the jet pump and,consequently, enables to determine the maximum permissible dimensions ofthe jet pump body that is of much importance, since the diameter of thewell is the main limiting factor when arranging equipment in the well.The possibility of replacing the sealing assembly with other functionalinserts and the possibility of placing, instead of the transmitter andreceiver-transducer of physical fields, other well instruments, inparticular a perforator, an ultrasonic transmitter, a sampling device, athermometer, a pressure gauge, etc., enables to conduct various works,e.g., to pressure-test the packer, transfer the well in the flow mode,conduct works on perforating the productive stratum and perform otheroperations without lifting the jet pump and the piping string from thewell. In the result, the possibilities of the well jet device inconducting studies and repair and restoration works in the well areexpanded and the time necessary for such works is shortened. Making ofinserts with the axis aligned with the axis of the through passageenables to reduce the possibility of inserts being stuck in the processof their installation or removal, which increases the reliability ofoperation of the well jet device.

[0014] Of no lesser importance is the rational organization of worksaimed at exploring the well, which enable to obtain more adequateinformation on the condition of the well and the productive stratum,and, due to it, accelerate the process of restoring the well output. Inparticular, background measurements of temperature and other physicalfields in the operation of lowering the transmitter andreceiver-transducer of physical fields enable to get, prior toinitiating inflow from the stratum, preliminary data on the presentcondition of the well, which makes it possible to elaborate practicalmeasures for exploring the well and more adequately interpret the wellexploration results in the mode of inflow from the stratum. Moving thetransmitter and receiver-transducer of physical fields along the well,especially in the area of the productive stratum, both when the jet pumpis operated or when it is shut down, enables to take dynamic and staticcharacteristics of the well. In the course of exploration it has beenfound that adequate accuracy of obtained data may be obtained whenmoving the transmitter and receiver-transducer of physical fields withthe speed from 0.1 to 100 meters per minute and at changing bottom-holepressure stepwise in the range from the normal stratum pressure to 0.01stratum pressure. The installation of the functional inserts enables,apart from the above-stated possibilities, to organize different modesof well operation, in particular, it becomes possible not only to getdata on the composition of the fluid coming from the productive stratum,but also take important characteristics of the well, such as record astratum pressure restoration curve in the area below the packer, thispossibility being achieved due to reduction in the bottom-hole pressureup to a value being 0.01 of nominal and subsequent sharp stopping ofsupply of the liquid working medium to the nozzle of the jet pump, and,what is most important, the well jet device enables to make recordingsrepeatedly at various modes in the above-stated range. As the result,the reliability of the obtained data is significantly improved. All theabove-indicated works may be conducted without numerous re-installationsof the equipment in the well, which improves the efficiency of the welljet device greatly. After the completion of a cycle of the works onexploring and restoring the well workability, the whole cycle may berepeated, also without the necessity to re-install the equipment in thewell. Thus, the scope of investigations carried out in the well has beenexpanded, which is of importance when carrying out restoration works.

[0015] In the result, the objective of the invention—to optimize-thesuccession of operations and the dimensions of various components of thewell jet device—has been achieved, and, owing to that, the efficiency ofoperation of the well jet device has been improved.

BRIEF DESCRIPTION OF DRAWINGS

[0016]FIG. 1 is a longitudinal section of the well jet device describedherein.

[0017]FIG. 2 is a longitudinal section of the well jet device with afunctional insert installed in the through passage.

PREFERRED EMBODIMENT OF THE INVENTION

[0018] The proposed well jet device for testing and developing wells,which is served to implement the described method, comprises the packer1, the piping string 2 and the jet pump 3, in the body 4 of which theactive nozzle 5 with the mixing chamber 6 are axially arranged and thestepped through passage 7 is made with the mounting seat 8 between stepsfor installing the sealing assembly 9 having the axial channel 10, thesaid device being provided with the transmitter and receiver-transducerof physical fields 11, which is arranged on the side of the jet pump 3for entry of the medium pumped out of the well and installed on thecable 12 (or a wire) fed through the axial passage 10 of the sealingassembly 9. The output side of the jet pump 3 is connected to the spacearound the piping string 2, the input side of the passage 13 in the jetpump 3 for supplying the pumped out medium is connected to the innercavity of the piping string 2 below the sealing assembly 9, and theinput side of the passage 14 for supplying the working medium to theactive nozzle 5 is connected to the inner cavity of the piping string 2above the sealing assembly 9. The through passage 7 of the jet pump 3 ismade parallel to the axis of the piping string 2, the diameter D₁ of thebigger step in the through passage 7, which is located above themounting seat 8 is at least 0.5 mm greater than the diameter D₂ of thestep in the through passage 7, which is located below the mounting seat8, the axis of the active nozzle 5 is parallel to the axis of thethrough passage 7 and is located at a distance L equal at least 1.1radii R of the bigger step of the through passage 7; the sealingassembly 9 is installed with the possibility of being replaced, e.g., inturns, by the functional inserts 15, namely, a hydrostatic testinginsert, a depression insert, a blocking insert an insert for recordingstratum pressure restoration curves and an insert for hydrodynamicimpact on the stratum; the axes of the sealing assembly 9 and thefunctional inserts 15 are in alignment with the axis of the throughpassage 7 in the jet pump 3; the diameter D₃ of the axial passage 10 inthe sealing assembly 9 is not greater than 0.6 outer diameter D₄ of thesealing assembly 9; the functional inserts 15 are made with thepossibility of installing on them autonomous well instruments andsampling devices 16 and are made with a tool 17 for delivery and removalof them from the jet pump 3 with the use of cable equipment, the sealingassembly 9 being installed with the possibility of moving it along thewell-logging cable 12 (or a wire) above the cap on which the transmitterand receiver-transducer of physical fields 11 is arranged, the latterbeing made with the possibility of operating it in the area under thepacker 1 when the jet pump 3 is operated and when it is shut down andbeing connected to the cap of the well-logging cable 12 (or a wire) withthe possibility of being replaced by other well instruments, e.g., aperforator, an ultrasonic transmitter, a sampling device, a thermometer,a pressure gauge, which all may be connected, either in turns orjointly, to the well-logging cable or a wire.

[0019] The described method of operation is implemented as follows.

[0020] The jet pump 3 and the packer 1 on the piping string 2 arelowered into the well and arranged above the productive stratum. Thepacker 1 is put into the operating position (release of the packer 1),thus separating the space surrounding the piping string 2 in the well.The sealing assembly 9 and the transmitter and receiver-transducer ofphysical fields 11 are lowered on the cable 12, the sealing assemblybeing put into position on the mounting seat 8 in the through passage 7and the transmitter and receiver-transducer being arranged below the jetpump 3. The sealing assembly 9 separates back and forth movements of thewell-logging cable 12 or a wire. When being lowered into the well, thetransmitter and receiver-transducer of physical fields 11 is used forbackground measurements of temperature and other physical fields in thespace before the well bottom (productive stratum). Thus, the transmitterand receiver-transducer of physical fields 11 is arranged in the stratuminterval under exploration. The working medium, e.g., water, saltsolution, oil, etc., is pumped in through the piping string 2. From thepiping string 2 the working medium flows through the passage 14 to theactive nozzle 5 of the jet pump 3. Within a few seconds after pumpingthe working medium through the active nozzle 5 a stable jet is formed atthe outlet of the nozzle and, flowing out of the nozzle 5, entrains thesurrounding medium into the jet pump, which results in a pressurereduction first in the passage 13 for supplying of the pumped out mediumand then in the under-packer space of the well. In the result, thestratum medium flows to the jet pump 3 through a section of the pipingstring 2 below the sealing assembly 9 and through the passage 13, whereit is mixed with the working medium, and the medium mixture flows fromthe well to the surface through the hole clearance around the pipingstring 2 due to the energy of the working medium. During pumping outseveral values of pressure drawdown on the productive stratum aresuccessively created. At each value of the pressure drawdown thewell-bottom pressure, the composition of the fluid coming from thestratum and the well output are registered. After that the parameters ofphysical fields are recorded while moving the transmitter andreceiver-transducer of physical fields 11 along the well with the speedfrom 0.1 to 100 meters per minute and at the well-bottom pressureschanging stepwise from the normal stratum pressure to 0.01 stratumpressure. The transmitter and receiver-transducer of physical fields isthus moved both when the jet pump 3 is operated and when it is shutdown. Then the transmitter and receiver-transducer of physical fields 11is removed from the well, and the functional insert 15, which isprovided with a pressure sensor and a sampling device 16, is lowered onthe well-logging cable 12 or a wire for the purpose of recording stratumpressure restoration curves, and installed in the through passage 7 ofthe jet pump 3. With the use of the jet pump 3 a required pressuredrawdown on the stratum is created, and, after sharp stopping of supplyof the liquid working medium to the jet pump 3, a stratum pressurerestoration curve for the under-packer well space is registered.Recording of stratum pressure restoration curves may be done repeatedlyat different values of the pressure drawdown on the stratum. Then theobtained measurements are processed, and a decision may be taken whetherrepairs of the well are necessary, which are conducted with the use ofthe jet pump 3 and alternatively changed functional inserts 15 as wellwith the use of instruments lowered into the well with the sealingassembly 9 on the well-logging cable .12 (or a wire), e.g., aperforator, an ultrasonic transmitter, a sampling device, a thermometeror a pressure gauge. Depending on the performed operations, a blockinginsert, a depression insert or a hydrostatic testing insert may beinstalled on the mounting seat 8 in the through passage 7. A blockinginsert is used for closing the passages in the jet pump 3 and ensuringthe well operation in the flow mode. A depression insert is used forseparation of the piping string 2, which ensures the operation of thejet pump 3. A hydrostatic testing insert is used for pressure testing ofthe well and the packer. After completion of the above-indicated worksthe whole cycle of well exploration may be repeated, if necessary.

Industrial Applicability

[0021] This invention may be used in testing, developing, operating andconducting work-over of oil and gas condensate wells, as well as inother industries where various media are extracted out of wells.

What is claimed is:
 1. The well jet device comprising a packer, a pipingstring and a jet pump, in the body of which an active nozzle with amixing chamber are arranged and a stepped through passage is made with amounting seat between steps for installing a sealing assembly having anaxial channel, the said device being provided with a transmitter and areceiver-transducer of physical fields, which is arranged at the jetpump side for entry of the medium pumped out of the well, the jet pumpoutput side is connected to the space around the piping string, theinput side of the jet pump passage for supplying the pumped out mediumis connected to the inner cavity of the piping string below the sealingassembly, and the input side of the passage for supplying the workingmedium to the active nozzle is connected to the inner cavity of thepiping string above the sealing assembly, and the through passage of thejet pump is made parallel to the axis of the piping string,characterized in that the axis of the active nozzle is parallel to theaxis of the through passage and being located from the latter's axis ata distance equal at least 1.1 radii of the bigger step of the throughpassage, the diameter of the bigger step in the through passage, whichis located above the mounting seat, is at least 0.5 mm greater than thediameter of the step in the through passage, which is located below themounting seat; the sealing assembly is arranged on the well-loggingcable or on a wire fed through the axial passage and installed with thepossibility of being replaced, e.g., in turns, by the functionalinserts, namely, a hydrostatic testing insert, a depression insert, ablocking insert, an insert for recording stratum pressure restorationcurves and an insert for hydrodynamic impact on the stratum, thediameter of the axial passage in the sealing assembly is not greaterthan 0.6 outer diameter of the sealing assembly; the axes of the sealingassembly and the functional inserts are aligned with the axis of thethrough passage in the jet pump; the functional inserts are made withthe possibility of installing on them autonomous well instruments andsampling devices and are made with a tool for delivery and removal ofthem from the jet pump with the use of cable equipment, the sealingassembly being installed with the possibility of moving it along thewell-logging cable or a wire above the cap on which the transmitter andreceiver-transducer of physical fields is arranged, the latter beingconnected to the well-logging cable cap with the possibility of beingreplaced by other well instruments, e.g., a perforator, an ultrasonictransmitter, a sampling device, a thermometer, a pressure gauge, whichall may be connected, either in turns or jointly, to the well-loggingcable or a wire.
 2. The method of operation of the well jet unit,including installation on the piping string of the packer and the jetpump having the through passage with the mounting seat, lowering of thatassembly into the well, release of the packer and arrangement in thewell, below the jet pump, of the transmitter and receiver-transducer ofphysical fields, characterized in that the said transmitter andreceiver-transducer of physical fields being lowered together with thesealing assembly arranged on the well-logging cable or a wire above thecap with the transmitter and receiver-transducer connected to thelatter, when lowering into the well, the transmitter andreceiver-transducer of physical fields is used for backgroundmeasurements of temperature and other physical fields before the wellbottom, the sealing assembly is installed onto the mounting seat in thethrough passage without impeding the back and forth motion of thewell-logging cable or wire, then the transmitter and receiver-transducerof physical fields is arranged in the stratum interval under explorationand, by supplying the working medium to the nozzle of the jet pump,several values of pressure drawdown on the stratum are successivelycreated, and, at each its value, bottom-hole pressures, compositions ofthe fluid coming from the stratum and the well flow rate are measured,after which the parameters of physical fields are recorded by moving thetransmitter and receiver-transducer of physical fields along the wellaxis in the speed range from 0.1 to 100 meters per minute and atbottom-hole pressures changing stepwise from the stratum pressure to0.01 stratum pressure, the transmitter and receiver transformer ofphysical fields being moved along the well axis both when the jet pumpis operated and when it is shut down; then the transmitter andreceiver-transducer of physical fields is lifted out of the well, andthe functional insert for recording stratum pressure restoration islowered, the said insert being provided with a pressure sensor and asampling device, installed in the through passage of the jet pump, arequired pressure drawdown on the stratum is created with the use of thejet pump, and, after sharp stopping of supplying the liquid workingmedium to the jet pump, a stratum pressure restoration curve for thewell zone under the packer is recorded, said recording of stratumpressure restoration curves may be done repeatedly at different pressuredrawdown on the stratum; after that the results are processed, and adecision is taken whether repair works on the well are necessary, suchworks being conducted with the use of the jet pump and the alternativelyapplied functional inserts being lowered into the well with the sealingassembly on the well-logging cable or wire and with, e.g., a perforator,an ultrasonic transmitter, a sampling device, a thermometer and apressure gauge; after completion of the said works the cycle of wellexploration is repeated.